Piercing device with retractable needle

ABSTRACT

A piercing device comprising a main body, a piercing needle and a stud member, in which said piercing needle protrudes in a first direction from a first slider, in which said first slider is mounted on a first track provided on said main body, and is reciprocally moveable along a piercing axis between a stand-by position and a piercing position, in which said stud member is removably mounted to second slider and protrudes therefrom in a second direction opposite to said first direction, in which said second slider is mounted on a second track and is moveable along said piercing axis in said second direction, in which said first slider comprises a first connector part and said second slider comprises a second connector part, in which in a first device configuration said first slider is in said stand-by position and is located relative to said second slider such that said first connector part is spaced from said second connector part, and in which in a second device configuration said first slider is in said piercing position and is located relative to said second slider such that said first connector part is engaged with said second connector part, and subsequent movement of said first slider in said second direction is transmitted to said second slider.

BACKGROUND

The present invention relates to a piercing device with a retractableneedle, for use particularly, but not exclusively, as an ear piercingdevice.

Ear piercing guns are known, and they comprise a main body, an ear lobecontainment area with a trigger operated sliding mechanism on one sideand a clasp mounted on the other side. Operation of the trigger drives astud mounted on the sliding mechanism through the ear containment areaalong a piercing axis, until it engages the clasp on the other side. Inuse the gun is offered up to the subject's ear until their ear lobe ispositioned as desired within the ear containment area. The trigger isoperated to drive the stud through the user's ear, and to connect it tothe clasp on the opposite side. The gun is then withdrawn leaving thestud and clasp in place on the subject's ear. Commonly the main bodycomprises a trigger housing and a single-use cartridge removably mountedthereon and engaged with the trigger mechanism. The trigger housing isre-usable, while the single-use cartridge is provided along with thestud and clasp for each subject. As such, no part of the reusabletrigger housing contacts the subject's skin. Ear piercing guns of thiskind are popular as they can be used by non-skilled practitioners. Themethod of use is simple, and no particular skills are needed.

However, ear piercing guns of this kind suffer from a number ofdrawbacks. Firstly, while the stud may have a sharp end to assist thepiercing process, it is still effectively just an earring with a solidpin. This means that the aperture which is formed in the subject's earlobe is a puncture. This is painful for the user because of the amountof pressure required and because of the resulting stress to thesurrounding tissue, and it also results in a comparatively roughaperture. As a result of this, and the fact that the instrument ofpiercing remains in situ, there is a relatively high chance ofsubsequent infection.

This is in contrast to when a body piercing needle is used manually by aprofessional body piercer. Such needles only serve to create thepiercing, and as such they can be formed with a sharp point to create aclean hole. The needles are commonly hollow, so they remove a smallamount of skin and tissue in the immediate area of the piercing wound.This procedure is less painful because less pressure is needed, and italso results in a cleaner and more effective piercing which can moreeasily heal. However, skill and experience is usually required.

Some known ear piercing guns comprise simple trigger mechanisms in whichthe trigger can be released from any position. The danger with this isthat the trigger can be released too early in the piercing process,which can result in a partial piercing. If so, it can be difficult tore-align the stud correctly for a second attempt without causing injury.

Another drawback with known ear piercing guns is that the stud isexposed to atmosphere for a period of time prior to insertion. Thecartridges are usually provided in sealed sterile packaging, but this isremoved when the cartridge is placed on the trigger housing. The pinpart of the stud is then exposed, which can lead to injury, or tocontamination prior to insertion.

Yet another drawback of known ear piercing guns is that the earcontainment area is usually a fixed width. This means that the subject'sear lobe may not be positioned correctly therein prior to insertion.There is no means to accurately secure the position of the gun relativeto the subject's ear.

The present invention is intended to overcome some of the abovedescribed problems.

SUMMARY

Therefore, according to the present invention a piercing devicecomprises a main body, a piercing needle and a stud member, in whichsaid piercing needle protrudes in a first direction from a first slider,in which said first slider is mounted on a first track provided on saidmain body, and is reciprocally moveable along a piercing axis between astand-by position and a piercing position, in which said stud member isremovably mounted to second slider and protrudes therefrom in a seconddirection opposite to said first direction, in which said second slideris mounted on a second track and is moveable along said piercing axis insaid second direction, in which said first slider comprises a firstconnector part and said second slider comprises a second connector part,in which in a first device configuration said first slider is in saidstand-by position and is located relative to said second slider suchthat said first connector part is spaced from said second connectorpart, and in which in a second device configuration said first slider isin said piercing position and is located relative to said second slidersuch that said first connector part is engaged with said secondconnector part, and subsequent movement of said first slider in saidsecond direction is transmitted to said second slider.

Thus, a piercing device is provided which is as easy to use as known earpiercing guns, but involves the use of a retractable needle to create asuperior piercing. Ease of use is further enhanced by the feature thatthe stud member is inserted into the piercing in the subject's ear atthe same time as the piercing needle is withdrawn. This simplifies theear piercing process by reducing the number of procedural steps, andalso ensures that the stud member is inserted cleanly into the piercingalong the exact same axis as the piercing needle.

Preferably the piercing device can comprise a clamp, which can comprisea static jaw and a sliding jaw with a containment area therebetween. Thesliding jaw can be mounted on a third track for movement along thepiercing axis, and the static jaw and sliding jaw can each comprise aneedle aperture on the piercing axis. The piercing device can furthercomprise a handle for moving the sliding jaw between an open positionand a clamping position. The static jaw and the sliding jaw can belocated on the piercing axis between the first slider and the secondslider, and the first slider can be located relative to the static jawsuch that the piercing needle can extend through the needle apertures inthe second device configuration.

The clamp allows the subject's ear lobe to be held securely in positionrelative to the piercing needle and stud member. The sliding jaw can bemoved back and forth to accommodate the subject's ear lobe. The piercingneedle the passes through them both as it is moved from the stand-byposition and the piercing position, and the stud member also passesthrough them both as it is then moved into position travelling in theopposite direction.

The piercing device can further comprise a needle sleeve, which can beprovided on a third slider, and which can comprise a first sectionextending through the third slider and a second section protruding inthe first direction from the third slider. The third slider can bemounted on the first track and can be reciprocally moveable along thepiercing axis between a retracted position and an advanced position. Thethird slider can be located on the piercing axis between the firstslider and the sliding jaw. The first slider can comprise a firstengagement surface facing in the first direction, and the third slidercan comprise a second engagement surface facing in the second direction.In the first device configuration the third slider can be in theretracted position and can be located relative to the first slider suchthat the first engagement surface is spaced from the second engagementsurface, but at least a tip of the needle is enclosed in the needlesleeve. In a third device configuration the first slider can be locatedin an intermediate position between the stand-by position and thepiercing position and relative to the third slider such that the firstengagement surface contacts the second engagement surface, andsubsequent movement of the first slider in the first direction moves thethird slider from the retracted position towards the advanced position.The needle sleeve can be dimensioned such that in the third deviceconfiguration the tip of the needle can protrude from the needle sleeve.The third slider can be positioned relative to the static jaw such thatthe needle sleeve extends through the needle apertures in the seconddevice configuration.

The needle sleeve performs two important functions. Firstly, in thefirst configuration, the tip of the piercing needle is enclosed in theneedle sleeve. This reduces the risk of injury, and prevents the tip ofthe piercing needle being openly exposed to atmosphere. Secondly, theneedle sleeve follows the piercing needle into the piercing and extendstherethrough. It then remains in situ as the piercing needle iswithdrawn, thereby maintaining the piercing aperture as the stud memberis then inserted from the other side.

Following on from the above the third slider can comprise a tail portionextending in the second direction therefrom, and a third connector partcan be provided at an outer end of the tail portion. The first slidercan comprise a fourth connector part, and in a fourth deviceconfiguration the third slider can be in the advanced position, thefirst connector part can be engaged with the second connector part, andthe first slider can be located relative to the third slider such thatthe third connector part can be engaged with the fourth connector part,and subsequent movement of the first slider in the second directionmoves the third slider from the advanced position towards the retractedposition. In the fourth device configuration an outer end of the studmember can be enclosed in the needle sleeve.

Therefore, once the piercing needle has been moved to the piercingposition and begins to move back towards the stand-by position, it dragsthe second slider with it, towards the needle sleeve which remainsstationary as the first slider has temporarily disconnected from thethird slider. The stud member travels into the needle sleeve inside thesubject's ear lobe, and is therefore not forced directly into the tissueof the subject's ear lobe. Once this has happened the fourth connectorpart of the first slider engages the third connector part at the outerend of the tail portion of the third slider, and drags the third sliderwith it, thereby withdrawing the needle sleeve from the piercing. Thefirst slider, second slider and third slider are then all connectedtogether and move in unison in the second direction. This occurs untilthe second slider contacts the static jaw, and cannot travel in thesecond direction any further. Further movement of the first slider inthe second direction leads to the first connector part disengaging fromthe second connector part. Further movement of the first slider andthird slider in the second direction leads to the sleeve withdrawingfrom the stud, leaving it in place in the ear piercing, in a fifthdevice configuration.

The tail portion can be dimensioned such that when the third connectorpart and the fourth connector part are engaged the first slider and thethird slider are spaced relative to one another as in the first deviceconfiguration, and in particular so the tip of the piercing needle isenclosed in the needle sleeve. This ensures that once the tip of thepiercing needle is withdrawn back into the needle sleeve it neverprotrudes therefrom again.

Preferably the first slider can comprise an opening through which thetail portion can extend, and a third engagement surface facing in thesecond direction. The third connector part can then comprise a flange atan outer end thereof with a greater diameter than the opening. In thefourth device configuration the flange can contact the third engagementsurface. This is an expedient and compact arrangement of engaging partswhich keeps the size of the mechanism to a minimum.

It will be appreciated from all the above that only the first slider isdriven to move, and it transmits movements to the second slider and thethird slider. In one version of the invention a motor can be provided tomove the first slider in all the ways described above. In anotherconstruction the first slider can be directly manually moveable by hand.However, in a preferred construction the piercing device can comprise atrigger, which can be connected to the first slider by a first linkageso movement of the trigger is transmitted thereto. The trigger can bemounted for movement on a first displacement mechanism provided on themain body, and it can be movable between a primed position in which thefirst slider is in the stand-by position, and a depressed position inwhich the first slider is in the piercing position.

The first displacement mechanism can be a pivot about which the triggercan rotate. However, in a preferred construction the first displacementmechanism can comprise an enclosure formed by the main body, and thetrigger can be reciprocally moveable along a linear trigger axis. Alinearly moving trigger provides a more suitable basis for the featuresdescribed below.

The first linkage can comprise a compound gear comprising a driver gearon a first rack provided on the trigger and a driven gear on a secondrack associated with the first slider. Thus, linear movement of thetrigger is transmitted to the first slider, and the relative linearmovements are controlled by the compound gear ratio.

In a preferred construction a first non-return ratchet can be disposedbetween the trigger and the main body which can prevent movement of thetrigger towards the primed position until the trigger is in thedepressed position. With this feature it is not possible for the firstslider and piercing needle to be moved in the second direction until thefirst slider has reached the piercing position. As such, the fullpiercing action must be performed, and cannot be deliberately orinadvertently reversed. This prevents any accidental part piercingtaking place.

The first non-return ratchet can be any known construction which iscapable of providing a non-return function. However, it must also allowthe trigger to return to the primed position, so as to allow for thefirst slider to be driven back to the stand-by position.

Preferably the first non-return ratchet can comprise a sheath providedon the main body and a rod associated with the trigger for relativereciprocal movement in the sheath in unison with movement of the triggeron the first displacement mechanism. The rod can comprise a plurality ofradially outwardly extending teeth and the sheath can comprise aplurality of radially inwardly extending ratchet slots for engaging theplurality of teeth in a non-return manner. The plurality of teeth canextend only partially around the rod circumferentially and the slots canextend only partially around the sheath circumferentially. The rod canthen comprise a radially outwardly extending boss and the sheath cancomprise a radially inwardly extending guide slot in which the boss isdisposed. The guide slot can extend in an axial direction of the sheathand can comprises a first portion, second portion, third portion andfourth portion. The first portion can be axially linear and candetermine a first axial rotational position of the boss when the triggeris in the primed position and when the trigger is travelling from theprimed position to the depressed position. In this first axialrotational position of the boss the teeth can be axially aligned withthe ratchet slots. The second portion can extend in a helical directionof the sheath and can transmit linear movement of the rod in the sheathinto a first axial rotation of the boss from the first axial rotationalposition to a second axial rotational position in which the teeth areaxially displaced from the ratchet slots. The third portion can beaxially linear and can determine the second axial rotational position ofthe boss when the trigger is in the depressed position and when thetrigger is travelling from the depressed position to the primedposition. Finally, the fourth portion can extend in a helical directionof the sheath and can transmit linear movement of the rod in the sheathinto a second axial rotation of the boss from the second axialrotational position back to the first axial rotational position.

Therefore, when the trigger is depressed the rod travels into thesheath, and the plurality of teeth are engaged by the plurality ofratchet slots to prevent the trigger from moving in the reversedirection. However, at the end of the trigger's depression the rod isaxially rotated as a result of the movement of the boss through thesecond portion of the guide slot. This displaces the teeth from theratchet slots and the trigger can then move back towards the primedposition. At the end of this reverse movement the rod is axially rotatedback again as a result of the movement of the boss through the fourthportion of the guide slot. The teeth are then re-aligned with theratchet slots.

At least one first spring member can be disposed between the trigger andthe main body which can bias the trigger towards the primed position.The first spring member therefore provides a force which urges the teethinto engagement with the ratchet slots, but which also drives thetrigger back to the primed position. This drive is transmitted to thefirst slider by the compound gear, and provides the motive force for thefirst slider to travel from the piecing position back to the stand-byposition, and for the various other actions associated with thatmovement to be performed, as explained above.

The piercing device can be a single device with all the above describedfeatures. However, in one embodiment of the invention the main body cancomprise a trigger housing and a needle cartridge removably mountedthereon. The needle cartridge can comprise the first slider, firsttrack, piercing needle, second slider, second track and stud member. Thefirst linkage can then comprise a first drive body disposed in thetrigger housing, and movement of the trigger from the primed position tothe depressed position can move the first drive body from a startposition to an end position. The first slider can comprise a firstinterface portion and the first drive body can comprise a secondinterface portion, and the first interface portion can interface withthe second interface portion when the needle cartridge is mounted to thetrigger housing, such that movement of the first drive body istransmitted to the first slider.

With this construction the piercing device can function like known earpiercing guns, with a single-use cartridge and a reusable tool. Thisallows the cartridge to be provided in sealed sterile packaging, whichcan be removed immediately prior to use. This minimises the chance ofinfection. It also allows the tool to be made from more expensive androbust materials as it will be reused many times.

Returning to the clamp feature, the handle can be connected to thesliding jaw by a second linkage so movement of the handle is transmittedthereto. The handle can be mounted on a second displacement mechanismprovided on the main body and can be movable between a rearward positionin which the sliding jaw is in the open position and a forward positionin which the sliding jaw is in the clamping position.

A second non-return ratchet can be disposed between the handle and themain body, and it can comprise a rack, a pawl member and a releasemechanism. The second non-return ratchet can prevent movement of thehandle towards the rearward position, unless the release mechanism isactivated. A second spring member can be disposed between the handle andthe main body which can bias the handle towards the rearward position.

Therefore, the clamp is operated by manual manipulation of the handle,which can be moved to drive the sliding jaw towards the static jaw andsecure the subject's ear lobe in position. The second non-return ratchetthen holds the sliding jaw in place, until the release mechanism isactivated, and the second spring drives the sliding jaw back to the openposition.

In versions of the invention in which the main body comprises a triggerhousing and a needle cartridge removably mounted thereon, the needlecartridge can comprise the first slider, first track, piercing needle,second slider, second track, stud member and the clamp. The secondlinkage can then comprise a second drive body disposed in the triggerhousing, and movement of the handle from the rearward position to theforward position can move the second drive body from a primary positionto a secondary position. The sliding jaw can comprise a third interfaceportion, and the second drive body can comprises a fourth interfaceportion. The third interface portion can interface with the fourthinterface portion when the needle cartridge is mounted to the triggerhousing, such that movement of the second drive body can be transmittedto the sliding jaw.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be performed in various ways, but one embodiment willnow be described by way of example, and with reference to theaccompanying drawings, in which:

FIG. 1 is a perspective view of a piercing device according to thepresent invention in a first device configuration;

FIG. 2 is a perspective view of the piercing device as shown in FIG. 1in a second device configuration;

FIG. 3 is a perspective view of internal components of the piercingdevice as shown in FIG. 1 ;

FIG. 4 is an exploded perspective view of the piercing device as shownin FIG. 1 ;

FIG. 5 is a cross-sectional side view of the piercing device shown inFIG. 1 in the first device configuration;

FIG. 6 is a cross-sectional side view of the piercing device shown inFIG. 1 in the first device configuration with a sliding jaw componentthereof in the clamping position;

FIG. 7 is a cross-sectional side view of the piercing device shown inFIG. 1 in the second device configuration;

FIG. 8 is a cross-sectional side view of the piercing device shown inFIG. 1 between the second device configuration and a fourth deviceconfiguration;

FIG. 9 is a cross-sectional side view of the piercing device shown inFIG. 1 in a fifth device configuration;

FIG. 10 is a cross-sectional side view of the piercing device shown inFIG. 1 in the fifth device configuration with the sliding jaw componentthereof in the open position;

FIG. 11 is a perspective view of a first non-return ratchet component ofthe piercing device shown in FIG. 1 ;

FIG. 12 is a cross-sectional side view of the first non-return ratchetcomponent as shown in FIG. 1 in a first position;

FIG. 13 is a cross-sectional side view of the first non-return ratchetcomponent as shown in FIG. 1 in a second position;

FIG. 14 is a cross-sectional side view of the first non-return ratchetcomponent as shown in FIG. 1 in a third position;

FIG. 15 is a cross-sectional side view of the first non-return ratchetcomponent as shown in FIG. 1 in a fourth position; and,

FIG. 16 is a cross-sectional side view of the first non-return ratchetcomponent as shown in FIG. 1 in a fifth position.

DETAILED DESCRIPTION

As shown in the Figures, a piercing device 1 comprises a main body 2, apiercing needle 3 and a stud member 4. The piercing needle 3 protrudesin a first direction A from a first slider 5. The first slider 5 ismounted on a first track 6 provided on the main body 2, and isreciprocally moveable along a piercing axis B-B between a stand-byposition, as shown in FIGS. 1 and 5 , and a piercing position, as shownin FIGS. 2 and 7 . The stud member 4 is removably mounted to secondslider 7 and protrudes therefrom in a second direction C opposite to thefirst direction A. The second slider 7 is mounted on a second track 8and is moveable along the piercing axis B-B in the second direction C.The first slider 5 comprises a first connector part, in the form ofcatches 28, and the second slider 7 comprises a second connector part,in the form of upstanding portion 29. In a first device configuration,as shown in FIGS. 1 and 5 , the first slider 5 is in the stand-byposition and is located relative to the second slider 7 such that thefirst connector part (28) is spaced from the second connector part (29).In a second device configuration, as shown in FIGS. 2 and 7 , the firstslider 5 is in the piercing position and is located relative to thesecond slider 7 such that the first connector part (28) is engaged withthe second connector part (29), and subsequent movement of the firstslider 5 in the second direction is transmitted to the second slider 7.

The piercing device 1 is made from moulded plastics materials. The mainbody 2 comprises a reusable trigger housing 11 and a single-use needlecartridge 12 removably mounted thereon. The trigger housing 11 comprisestwo side pieces 13 and 14 which are joined together, and which formvarious of the internal spaces and features described below. Numerousparts are housed inside the trigger housing 11, and are supportedthereby. Likewise, the needle cartridge 12 also comprises two sidepieces 15 and 16 which are joined together, and which also form variousof the internal spaces and features described below. Again, numerousparts are housed inside the needle cartridge 12, and are supportedthereby.

The needle cartridge 12 comprises a first pair of opposed internalslots, one of which 17 is visible in FIGS. 5 to 10 , which are mouldedinto the side pieces 15 and 16 thereof. The first pair of internal slots17 provide both the first track 6 and the second track 8, upon which thefirst slider 5 and the second slider 7 travel back and forth, asdescribed further below. The needle cartridge 12 also comprises a secondpair of opposed internal slots, one of which 18 is visible in FIGS. 5and 10 , which are also moulded into the side pieces 15 and 16 thereof.The second pair of internal slots 18 are directly below the first pairor internal slots 17, and provide a third track 19. The needle cartridge12 also comprises a third pair of opposed internal slots 20, which arealso moulded into the side pieces 15 and 16 thereof. The third pair ofinternal slots 20 are above the first pair or internal slots 17, andprovide a fourth track 21.

Referring to FIG. 3 , the first slider 5 comprises a first pair oflateral tabs 22, which are disposed in the first track 6. Likewise, thesecond slider 7 comprises a second pair of lateral tabs 23, which aredisposed in the second track 8. The second slider 7 also comprises asupplementary pair of lateral tabs 24, which are disposed in the thirdtrack 19 below. This provides additional support for the second slider7.

As is clear from FIGS. 2 and 3 , the first slider 5 comprises a pair ofresilient arms 25, the outer ends 26 of which comprise rounded ends 27and catches 28. The resilient arms 25 are disposed in the fourth track21, which supports them for movement, although the arms 25 extendtherefrom in the second device configuration shown in FIGS. 2 and 7 .The two catches 28 comprise the first connector part referred to above.The second slider 7 comprises an upstanding portion 29 which comprisesthe second connector part referred to above. When the first slider 5 isdriven towards the second slider 7 in use the rounded ends 27 areapplied to the upstanding portion 29, and the resilient arms 25 flexoutwardly until the upstanding portion 29 is captured in the catches 28.Subsequent movement of the first slider 5 in the second direction isthereby transmitted to the second slider 7.

The upstanding portion 29 comprises a stud member socket 30 comprisingan top opening 31 and a front opening 32. A head portion 33 of the studmember 4 fits into the stud socket 30 via the top opening 31, with a pinportion 34 thereof extending out from the front opening 31.

The piercing device 1 comprises a clamp 35, which comprises a static jaw36 and a sliding jaw 37 with a containment area 38 therebetween. Thestatic jaw 36 is fixed in place between the two side pieces 15 and 16 ofthe needle cartridge 12, and doesn't move. The sliding jaw 37 is mountedon the third track 19 for movement along the piercing axis B-B. Itcomprises a third pair of lateral tabs 39 which are disposed in thethird track 19. The static jaw 36 and the sliding jaw 37 each comprise aneedle aperture 40 and 41 respectively on the piercing axis B-B.

A handle 42 is provided for moving the sliding jaw 37 between an openposition, as shown in FIGS. 1 and 5 , and a clamping positon, as shownin FIGS. 2 and 6 . The clamping position shown in FIGS. 2 and 6 isartificial because the sliding jaw 37 abuts against the static jaw 36,and nothing is clamped between them. The device 1 is shown in thefigures in this configuration for illustrative purposes only, and todemonstrate the full range of movement of the sliding jaw 37. In use theclamping position adopted each time will be the position the sliding jaw37 assumes when the subject's ear lobe (not shown) is located in thecontainment area 38, and is clamped between the static jaw 36 and thesliding jaw 37.

The handle 42 comprises a pair of laterally extending bars, only one ofwhich 43 is visible in the Figures, which extend out of side openings,only one of which 45 is visible in the Figures, in the respective sidepieces 13 and 14 of the trigger housing 11. The action and movement ofthe handle 42 is described in further detail below.

As is clear from the Figures, the static jaw 36 and the sliding jaw 37are located on the piercing axis B-B between the first slider 5 and thesecond slider 7. As shown in FIG. 7 the first slider 5 is locatedrelative to the static jaw 36 such that the piercing needle 3 extendsthrough both of the needle apertures 40 and 41 in the second deviceconfiguration. As such, the piercing needle 3 will always travelcompletely through the subject's ear lobe in the containment area 38.

The piercing device 1 further comprises a needle sleeve 47, which isprovided on a third slider 48. The needle sleeve 47 comprises a firstsection 49 extending through the third 48 slider and a second section 50protruding in the first direction A from the third slider 48. The thirdslider 48 comprises a fourth pair of lateral tabs 46, which are disposedin the first track 6, and it is reciprocally moveable along the piercingaxis B-B between a retracted position, as shown in FIG. 5 , and anadvanced position, as shown in FIGS. 2 and 7 . The third slider 48 islocated on the piercing axis B-B between the first slider 5 and thesliding jaw 37. The first slider 5 comprises a first engagement surface51 facing in the first direction A, and the third slider 48 comprises asecond engagement surface 52 facing in the second direction C.

In the first device configuration as shown in FIG. 5 , the third slider48 is in the retracted position and is located relative to the firstslider 5 such that the first engagement surface 51 is spaced from thesecond engagement surface 52, but at least a tip 53 of the piercingneedle 3 is enclosed in the needle sleeve 47. In a third deviceconfiguration, not shown, the first slider 5 is located in anintermediate position between the stand-by position shown in FIG. 5 andthe piercing position shown in FIG. 7 , in which it is positionedrelative to the third slider 48 such that the first engagement surface51 contacts the second engagement surface 52, and subsequent movement ofthe first slider 5 in the first direction A moves the third slider 48from the retracted position towards the advanced position. The needlesleeve 47 is dimensioned such that in the third device configuration thetip 53 of the piercing needle 3 protrudes from the needle sleeve 47(this is illustrated in FIG. 7 , in which the first engagement surface51 is contacting the second engagement surface 52 in the same way.) Thethird slider 48 is positioned relative to the static jaw 36 that theneedle sleeve 47 extends through the needle apertures 40 and 41 in thesecond device configuration, as shown in FIG. 7 .

Referring to FIG. 3 , the first slider 5 comprises an opening 54, andthe third slider 48 comprises a tail portion 55 extending in the seconddirection C therefrom, which extends through the opening 54. The firstslider 5 comprises a flange socket 56 facing in the second direction C,and a flange 57 is provided at an outer end 58 of the tail portion 55which has a greater diameter than the opening 54. Therefore, in a fourthdevice configuration, not shown, the third slider 48 is still in theadvanced position it has been driven to, and the first slider 5 isconnected to the second slider 7. However, the first slider 5 has movedback towards the stand-by position until it is located relative to thethird slider 48 for the flange 57 to slot into the flange socket 56. Assuch, subsequent movement of the first slider 5 in the second directionmoves the third slider 48 from the advanced position back towards theretracted position. FIG. 8 shows the components arranged just prior tothe fourth configuration being assumed, as the flange 57 is about to becollected by the flange socket 56.

The length of the tail portion 55 is such that two important effects areachieved. Firstly, in the fourth device configuration an end portion 59of the stud member 4 is enclosed in the needle sleeve 47 (this isachieved already in the position shown in FIG. 8 ). Therefore, once thepiercing needle 3 has passed through the containment area 38 there isnever a period during which no part of the piercing device 1 extendsthrough the containment area 38, and hence through the subject's earlobe. The end portion 59 of the stud member 4 is already enclosed in theneedle sleeve 47 before the needle sleeve 47 moves in the seconddirection C. As such, the piercing formed in the subject's ear lobe ismaintained by the needle sleeve 47 as the stud member 4 is moved intoposition. This results in a smooth and relatively painless insertion ofthe stud member 4.

The second effect of the length of the tail portion 55 is that in thefourth device configuration the first slider 5 and the third slider 48are spaced relative to one another as in the first device configuration,and in particular so the tip 53 of the piercing needle 3 is enclosed inthe needle sleeve 47. This ensures that once the tip 53 of the piercingneedle 3 is withdrawn back into the needle sleeve 47 it never protrudestherefrom again.

The piercing device 1 comprises a trigger 60, which is supported forlinear reciprocal movement in a trigger enclosure 61 formed by thetrigger housing 11. The trigger 60 comprises two moulded side pieces 62and 63 which are joined together, in order to form a solid unit formanual manipulation, but also to provide internal spaces for othercomponents, as described further below.

The trigger 60 is connected to the first slider 5 by a first linkage,generally designated 64, so movement of the trigger 60 is transmittedthereto. The trigger 60 is manually movable between a primed position asshown in FIGS. 1 and 5 , in which the first slider 5 is in the stand-byposition, and a depressed position as shown in FIG. 7 , in which thefirst slider 5 is in the piercing position.

The first linkage 64 comprises a compound gear 65 and a first drive body66, which are disposed in the trigger housing 11. The compound gear 65comprises a driver gear 67 (visible in FIG. 3 ) on a first rack 68provided on the trigger 60, and a driven gear 69 on a second rack 70provided on the first drive body 66. The compound gear 65 is supportedon a spindle 71 mounted between the side pieces 13 and 14 of the triggerhousing 11.

Therefore, movement of the trigger 60 from the primed position to thedepressed position moves the first drive body 66 from a start positionas shown in FIG. 5 , to an end position as shown in FIG. 7 .

The first slider 5 comprises a first interface portion in the form offirst socket 74 (visible in FIG. 3 ), and the first drive body 66comprises a second interface portion in the form of upstanding tab 75.The upstanding tab 75 is removably located in the first socket 74 whenthe needle cartridge 12 is mounted to the trigger housing 11. Theupstanding tab 75 and the first socket 74 interface with one anothersuch that all movement of the first drive body 66 is transmitted to thefirst slider 5. Thus, linear movement of the trigger 60 is transmittedto the first slider 5 via the first linkage 64, and the relative linearmovements thereof are controlled by the compound gear ratio. As is clearfrom the Figures, this is approximately 1:2.

A non-return ratchet 76 is disposed in the trigger enclosure 61 betweenthe trigger 60 and the trigger housing 11, which prevents movement ofthe trigger 60 towards the primed position until the trigger 60 is inthe depressed position. The non-return ratchet 76 comprises a sheath 77mounted to the trigger housing 11, and a rod 78 mounted to the trigger60 for relative reciprocal movement in the sheath 77 in unison withmovement of the trigger 60 in the trigger enclosure 61.

Referring to FIGS. 11 and 12 , the sheath 77 comprises a tubular part79, which has a lateral opening 80 formed therein. Disposed in oppositesides of the lateral opening 80 are opposed first ratchet member 81 andsecond ratchet member 82, each of which comprises a pair of stop tabs 83which delimit their travel into the lateral opening 80 beyond theposition shown in FIGS. 11 and 12 . Disposed around the tubular part 79and over the first and second ratchet members 81 and 82 are clip springs84 and 85, which bias the first and second ratchet members 81 and 82into the lateral opening 80. The clip springs 84 and 85 are preventedfrom moving axially on the tubular part 79 by the stop tabs 83, and bycentral tabs 86 provided between the stop tabs 83. The first and secondratchet members 81 and 82 each comprise a plurality of radially inwardlyextending ratchet slots 87. As is clear from FIG. 12 , the ratchet slots87 each comprise a first face 88 which is inclined relative to the rod78, and a second face 89 which is orthogonal to the rod 78. Each of thefirst and second ratchet members 81 and 82 also comprise an initial face90 which is inclined relative to the rod 78. As the ratchet slots 87 areonly provided on the first and second ratchet members 81 and 82 on noton the tubular part 79, they extend only partially around the sheath 77circumferentially. An inner end 91 of the sheath 77 is mounted in asheath socket 92 provided in the trigger enclosure 61.

The rod 78 comprises a plurality of radially outwardly extending teeth93, which are engaged in a non-return manner in use by the plurality ofratchet slots 87. As is clear in FIG. 11 the plurality of teeth 93comprise a first set 94 which extend only partially around the rod 78circumferentially, and which are engaged in use by the first ratchetmember 81, and a second set 95 which extend only partially around therod 78 circumferentially, and which are engaged in use by the secondratchet member 82. An outer end 96 of the rod 78 is mounted in a rodsocket 97 provided on the trigger 60.

Therefore, when the trigger 60 is manually depressed in use the rod 78is driven into the sheath 77. The teeth 93 are firstly forced againstthe initial faces 90 of the first and second ratchet members 81 and 82,which drives them radially outwardly against the compression force ofthe clip springs 84 and 85. Once the teeth 93 have moved past theinitial faces 90 the first and second ratchet members 81 and 82 areforced back towards the rod 78 by the clip spring 84 and 85. From thatpoint the same action is performed as the teeth 93 move down the ratchetslots 87 in turn. As the second faces 89 of the ratchet slots 87 areorthogonal to the rod 78, it cannot move back the way it came becausethe teeth 93 are held in place.

Referring to FIG. 11 , the rod 78 comprises a first radially outwardlyextending boss 98 and a second radially outwardly extending boss 99diametrically opposed to the first boss 98. The sheath 77 then comprisesa first radially inwardly extending guide slot 100 and a second radiallyinwardly extending guide slot 101 diametrically opposed to the firstguide slot 100. The first and second bosses 98 and 99 are disposed inthe first and second guide slots 100 and 101 respectively.

Each of the first and second guide slots 100 and 101 extends in an axialdirection of the sheath 77 and comprises a first portion 102, secondportion 103, third portion 104 and fourth portion 105. In each case thefirst portion 102 is axially linear and determines a first axialrotational position of the respective boss 98 or 99 when the trigger 60is in the primed position, as illustrated in FIG. 12 , and when thetrigger 60 is travelling from the primed position to the depressedposition, as illustrated in FIG. 13 . As is clear from these figures inthe first axial rotational position of the first and second bosses 98and 99 the teeth 93 are axially aligned with the ratchet slots 87. Assuch, the first non-return ratchet 76 functions to allow the trigger 60to be depressed, but prevents it from travelling back towards the primedposition. The interaction of the teeth 93 and the ratchet slots 87 alsocreates a perceptible indication felt by the user.

In each case the second portion 103 extends in a helical direction ofthe sheath 77 and transmits linear movement of the rod 78 in the sheath77 into a first axial rotation of the first and second bosses 98 and 99from the first axial rotational position to a second axial rotationalposition in which the teeth 93 are axially displaced from the ratchetslots 87, as illustrated in FIG. 14 . In each case the second portion102 is provided towards the inner internal end 106 of the sheath 77, sothis rotation of the rod 78 occurs as the trigger 60 reaches the end ofits movement into the depressed position. Therefore, once the trigger 60is fully depressed it is then free to return back towards the primedposition as the teeth 93 are no longer restrained by the ratchet slots87.

In each case the third portion 104 is axially linear and the first andsecond bosses 98 and 99 travel along it in the second axial rotationalposition. As such, the rod 78 is maintained in this position in whichthe teeth 93 are displaced from the ratchet slots 87 as the trigger 60moves back from the depressed position towards the primed positon, asillustrated by FIG. 15 .

In each case the fourth portion 105 extends in a helical direction ofthe sheath 77 and transmits linear movement of the rod 78 in the sheath77 into a second axial rotation of the first and second bosses 98 and 99from the second axial rotational position back to the first axialrotational position, at which the teeth 93 are once again aligned withthe ratchet slots 87, as illustrated in FIG. 16 . In each case thefourth portion 105 is provided towards an outer internal end 106 a ofthe sheath 77, so this rotation of the rod 78 occurs as the trigger 60reaches the end of its movement back into the primed position.Therefore, once the trigger 60 has returned to the primed position it isthen back in the correct position for a repeat of the action describedabove.

It will be appreciated that the manner in which the first non-returnratchet 76 controls the movement of the trigger 60 is transmitted viathe trigger 60, the first linkage 64 and the first slider 5 to thepiercing needle 3. As such, the piercing needle 3 cannot be moved in thesecond direction until the rod 78 is free to return back out from thesheath 77. This means that the piercing action of the piercing needle 3through the containment area 38 cannot be deliberately or inadvertentlyreversed. This prevents any accidental part piercing taking place.

A first coil spring 107 and a second coil spring 108 are disposed in thetrigger enclosure 61 between the trigger 60 and the trigger housing 11.The first and second coil springs 107 and 108 bias the trigger 60towards the primed position. This achieves three functions. Firstly, itprovides a dampening resistance to the depression of the trigger 60, soits position is controlled and a smooth action is achieved. Secondly, itprovides a force which urges the teeth 93 into engagement with theratchet slots 87, and the second faces 89 in particular. Thirdly, italso provides a force which drives the trigger 60 back to the primedposition. This drive is transmitted via the first linkage 64 to thefirst slider 5, and provides the motive force for the first slider 5 totravel from the piecing position back to the stand-by position, and forthe various other actions associated with that movement to be performed,as explained above.

Referring back to FIG. 3 , the handle 42 comprises a lever 109, a lowerend 110 of which is pivotally mounted between the side pieces 13 and 14of the trigger housing 11. As such, the handle is movable between arearward position, as shown in FIGS. 1 and 5 , in which the sliding jaw37 is in the open position, and a forward position, as shown in FIGS. 2,3 and 6 in which the sliding jaw 37 is in the clamping position.

The handle 42 is connected to the sliding jaw 37 by a second linkage 111so movement of the handle 42 is transmitted thereto. The second linkage111 comprises a second drive body 112 mounted for reciprocal linearmovement inside the trigger housing 11. The trigger housing 11 comprisesa fourth pair of internal slots, one of which 113 is visible in FIG. 6 ,formed in the side pieces 13 and 14 thereof, which form a fifth track114. The second drive body 112 comprises a fifth pair of lateral tabs115, one of which is visible in FIG. 3 , which are located in the fifthtrack 114.

The handle 42 is connected to the second drive body 112 by means oflaterally extending bars 43 being disposed in lateral recesses, only oneof which 116 is visible in FIG. 3 , provided in the second drive body112.

The sliding jaw 37 comprises a third interface portion, in the form ofdownwardly depending tab 117, and the second drive body 112 comprises afourth interface portion in the form of second socket 118. Thedownwardly depending tab 117 is removably located in the second socket118 when the needle cartridge 12 is mounted to the trigger housing 11,as shown in FIG. 5 . The downwardly depending tab 117 and the secondsocket 118 interface with one another such that all movement of thesecond drive body 112 is transmitted to the sliding jaw 37. Thus,pivoting movement of the handle 42 is transmitted to the sliding jaw 37via the second linkage 111. The distance the laterally extending bars 43travel circumferentially about the lower end 110 equates to the thelinear distance the sliding jaw 37 is moved.

A second non-return ratchet 119 is disposed between the handle 42 andthe trigger housing 11. This comprises a third rack 120 provided on anunderside 121 of the second drive body 112 and a pawl member in the formof leaf spring 122 which is mounted in a leaf spring socket 123 providedon the trigger housing 11. A release mechanism is provided in the formof button 124, which is mounted in button socket 125 provided on thetrigger housing 11. When the handle 42 is moved from the rearwardposition shown in FIG. 5 to the forward position shown in FIG. 6 thethird rack 120 is moved over the leaf spring 122, and the leaf spring122 acts against the third rack 120 to prevent it travelling back.Therefore, when the handle 42 is manually manipulated to move thesliding jaw 37 into a clamping position in use, the sliding jaw 37 isheld in the final position achieved. This acts to hold the subject's earlobe in the containment area 38.

To release the sliding jaw 37 the button 124 is depressed as shown inFIG. 10 , and a finger part 126 thereof pushes the leaf spring 122 inthe first direction A, which displaces it from the third rack 120. Thesecond drive body 112 is then free to return back to its primaryposition, which moves the sliding jaw 37 back to its open position.

A third coil spring 127 is disposed in the trigger housing 11 betweenthe second drive body 112 and a third coil spring socket 128. The thirdcoil spring 127 biases the handle 42 towards its rearward position. Thisachieves three functions. Firstly, it provides a dampening resistance tothe rotation of the handle 42, so its position is controlled and asmooth action is achieved. Secondly, it provides a force which urges theleaf spring 122 into engagement with the third rack 120. Thirdly, italso provides a force which drives the second drive body 112 back to itsprimary position when second non-return ratchet 119 is released as aresult of the button 124 being depressed.

Referring back to FIG. 4 , this shows the single use needle cartridge 12separate from the multi-use trigger housing 11. As explained above, theneedle cartridge 12 comprise the first slider 5, second slider 7, thirdslider 48, static jaw 36 and sliding jaw 37, as well as the piercingneedle 3, needle sleeve 47 and stud member 4. It also comprises latches129 and 130 which are a removable snap-fit in catches 131 and 132respectively provided on the trigger housing 11. Latch 129 comprises arelease button 133 which is accessible through a release opening 134 onthe trigger housing 11.

In use the piercing device 1 operates as follows. The needle cartridge12 is provided in sealed sterile packaging, which is removed immediatelyprior to use. The needle cartridge 12 is then attached to the triggerhousing 11 by means of the latches 129 and 130 and catches 131 and 132.When this happens the upstanding tab 75 on the first drive body 66engages the first socket 74 on the first slider 5, and the downwardlydepending tab 117 on the sliding jaw 37 engages the second socket 118 onthe second drive body 112.

The piercing device 1 is then offered up to the subject's head, untiltheir earlobe (not shown) is positioned as desired in the containmentarea 38. The user then manually pushes the handle 42 from its rearwardposition until the subject's ear lobe is secured between the static jaw36 and the sliding jaw 37. Movement of the handle 42 is transmitted tothe sliding jaw 37 by the second linkage 111, and namely by means of thesecond drive body 112 travelling in the first direction A down the fifthtrack 114, which moves the sliding jaw 36 above it in the same directiondown the third track 19. The second non-return ratchet 119 ensures thatthe sliding jaw 37 remains in the clamping position achieved.

The user then manually depresses the trigger 60 from its primed positionall the way to its depressed position. This should be done in a singleswift action. Movement of the trigger 60 is transmitted to the firstslider 5 by the first linkage 64, and the first non-return ratchet 76ensures that once it has begun travelling in the first direction A onthe first track 6 the first slider 5 can only continue on until it hasreached the piercing position.

Once the first slider 5 starts to move in the first direction A thepiercing needle 3 travels along the piercing axis B-B and through theneedle sleeve 47 until the tip 53 protrudes therefrom. During itsmovement the first slider 5 collects the third slider 48, because thefirst engagement surface 51 comes into contract with the secondengagement surface 52. The first slider 5 and third slider 48 then movecollectively in the first direction A along the piercing axis B-B, whichresults in the piercing needle 3 and the needle sleeve 47 travellingalong the piercing axis B-B though the needle aperture 41 of the slidingjaw 37, the subject's ear lobe, and then the needle aperture 40 of thestatic jaw 36.

As the first slider 5 approaches its piercing position the rounded ends27 of the pair of resilient arms 25 are applied to the upstandingportion 29 of the second slider 7, and the arms 25 flex outwardly untilthe upstanding portion 29 is captured in the catches 28. The firstslider 5 and second slider 7 are then connected together, as shown inFIGS. 2, 3 and 7 .

As the trigger 60 approaches its depressed position the first and secondbosses 98 and 99 are rotated into the second axial rotational positionin which the teeth 93 are axially displaced from the ratchet slots 87.As such, the user can then manually release the trigger 60, and it isdriven back into its primed position by the extension force of the firstand second coil springs 107 and 108. This movement of the trigger 60 istransmitted to the first slider 5 by the first linkage 64.

Once the first slider 5 starts to move along the piercing axis B-B inthe second direction C on the first track 6 the piercing needle 3travels back through the needle sleeve 47, so the tip 53 is enclosedthereby. This occurs because initially the movement of the first slider5 is not transmitted to the third slider 48. In addition, as the firstslider 5 is connected to the second slider 7, it travels along thepiercing axis B-B in the second direction C on the second track 8, andthe outer end 59 of the stud member 4 enters the needle sleeve 47.

These movements continue until the flange socket 56 of the first slider5 collects the flange 57 on the tail portion 55 of the third slider 48.From that point the first slider 5, second slider 7 and third slider 48move in unison in the second direction C, on the first track 6 andsecond track 8 accordingly. As such, the stud member 4 and the needlesleeve 47 move in unison back through the subject's ear lobe. Therefore,once the piercing needle 3 has passed through subject's ear lobe thereis never a period during which no part of the piercing device 1 extendsthrough the subject's ear lobe. In particular, the piercing formed inthe subject's ear lobe is maintained by the needle sleeve 47 as the studmember 4 is moved into position. This results in a smooth and relativelypainless insertion of the stud member 4.

The first slider 5, second slider 7 and third slider 48 move in unisonin the second direction until the second slider 7 comes into contactwith the static jaw 36 as shown in FIG. 9 . As the second slider 7 isprevented from travelling any further in the second direction the arms25 flex outwardly until the upstanding portion 29 is released from thecatches 28. The first slider 5 and second slider 7 are then disconnectedfrom one another. By this point the stud member 4 is in position in thesubject's ear lobe.

The first slider 5 and the third slider 48 continue back on the firsttrack 6 to their stand-by and retracted positions respectively, underthe extension force of the first and second coil springs 107 and 108,which is transmitted to them via the trigger 60 and the first linkage 64

The user then presses the button 124 to release the sliding jaw 37, andit is moved back to its open position on the third track 19 by theextension force of the third coil spring 124 acting on the second drivebody 112. The piercing device 1 is then withdrawn from the subject's earlobe. The stud member 4 leaves the stud socket 30 through the topopening 31, and remains in situ in the subject's ear lobe. A claspmember of some kind (not shown) can then be affixed to the outer end 59of the stud member 4, to keep it in place.

The single use needle cartridge 12 is then manually removed from thetrigger housing 11, by depressing the release button 133, whichdisengages latch 129 from the catch 131. The needle cartridge 12 is thendisposed of. As such the piercing device 1 functions like known earpiercing guns, with a single-use cartridge and the trigger housing 11 asa reusable tool.

The above described embodiment can be altered without departing from thescope of claim 1. For example, in one alternative embodiment a piercingdevice (not shown) comprises a unitary main body comprising all theabove described moving parts.

In another alternative embodiment (not shown) a motor is provided todrive the first slider in the first direction as opposed to a manuallymanipulated trigger.

In another alternative embodiment (not shown) the trigger can be mountedon a pivot for rotation, as opposed to being mounted in an enclosure forlinear movement.

Therefore, the present invention provides a piercing device which is aseasy to use as known ear piercing guns, but involves the use of aretractable needle to create a superior piercing. Ease of use is furtherenhanced by the feature that the stud member is automatically insertedinto the piercing in the subject's ear lobe at the same time as thepiercing needle is withdrawn. This simplifies the ear piercing processby reducing the number of procedural steps, and also ensures that thestud is inserted cleanly into the piercing along the exact same axis asthe piercing needle. In addition, the piercing device of the inventionalso provides a clamp which allows the subject's ear lobe to be heldsecurely in position relative to the piercing needle and stud, whichimproves the accuracy and functionality of the device. Furthermore, thepiercing device of the invention also incorporates a needle sleeve whichencloses the piercing needle to reduce the risk of injury and preventthe tip of the needle being openly exposed to atmosphere. The needlesleeve follows the piercing needle into the piercing and extendstherethrough, and remains in situ as the needle is withdrawn, therebymaintaining the piercing aperture.

We claim:
 1. A piercing device comprising a main body, a piercing needleand a stud member, in which said piercing needle protrudes in a firstdirection from a first slider, in which said first slider is mounted ona first track provided on said main body, and is reciprocally moveablealong a piercing axis between a stand-by position and a piercingposition, in which said stud member is removably mounted to secondslider and protrudes therefrom in a second direction opposite to saidfirst direction, in which said second slider is mounted on a secondtrack and is moveable along said piercing axis in said second direction,in which said first slider comprises a first connector part and saidsecond slider comprises a second connector part, in which in a firstdevice configuration said first slider is in said stand-by position andis located relative to said second slider such that said first connectorpart is spaced from said second connector part, and in which in a seconddevice configuration said first slider is in said piercing position andis located relative to said second slider such that said first connectorpart is engaged with said second connector part, and subsequent movementof said first slider in said second direction is transmitted to saidsecond slider.
 2. A piercing device as claimed in claim 1 furthercomprising a clamp, in which said clamp comprises a static jaw and asliding jaw with a containment area therebetween, in which said slidingjaw is mounted on a third track for movement along said piercing axis,in which said static jaw and said sliding jaw each comprise a needleaperture on said piercing axis, in which said piercing device comprisesa handle for moving said sliding jaw between an open position and aclamping position, in which said static jaw and said sliding jaw arelocated on said piercing axis between said first slider and said secondslider, and in which said first slider is located relative to saidstatic jaw such that said piercing needle extends through said needleapertures in said second device configuration.
 3. A piercing device asclaimed in claim 2 further comprising a needle sleeve, in which saidneedle sleeve is provided on a third slider and comprises a firstsection extending through said third slider and a second sectionprotruding in said first direction from said third slider, in which saidthird slider is mounted on said first track and is reciprocally moveablealong said piercing axis between a retracted position and an advancedposition, in which said third slider is located on said piercing axisbetween said first slider and said sliding jaw, in which said firstslider comprises a first engagement surface facing in said firstdirection, in which said third slider comprises a second engagementsurface facing in said second direction, in which in said first deviceconfiguration said third slider is in said retracted position and islocated relative to said first slider such that said first engagementsurface is spaced from said second engagement surface, but at least atip of said needle is enclosed in said needle sleeve, in which in athird device configuration said first slider is located in anintermediate position between said stand-by position and said piercingposition and relative to said third slider such that said firstengagement surface contacts said second engagement surface, andsubsequent movement of said first slider in said first direction movessaid third slider from said retracted position towards said advancedposition, in which said needle sleeve is dimensioned such that in saidthird device configuration said tip of said needle protrudes from saidneedle sleeve, and in which said third slider is positioned relative tosaid static jaw such that said needle sleeve extends through said needleapertures in said second device configuration.
 4. An ear piercing deviceas claimed in claim 3 in which said third slider comprises a tailportion extending in said second direction therefrom, in which a thirdconnector part is provided at an outer end of said tail portion, inwhich said first slider comprises a fourth connector part, in which in afourth device configuration said third slider is in said advancedposition, said first connector part is engaged with said secondconnector part, and said first slider is located relative to said thirdslider such that said third connector part is engaged with said fourthconnector part, and subsequent movement of said first slider in saidsecond direction moves said third slider from said advanced positiontowards said retracted position, and in which in said fourth deviceconfiguration an end portion of said stud member is enclosed in saidneedle sleeve.
 5. An ear piercing device as claimed in claim 4 in whichsaid first slider comprises an opening through which said tail portionextends and a third engagement surface facing in said second direction,in which said third connector part comprises a flange at an outer endthereof with a greater diameter than said opening, and in which in saidfourth device configuration said flange contacts said third engagementsurface.
 6. An ear piercing device as claimed in claim 1 furthercomprising a trigger, in which said trigger is connected to said firstslider by a first linkage so movement of said trigger is transmittedthereto, in which said trigger is mounted for movement on a firstdisplacement mechanism provided on said main body, and in which saidtrigger is movable between a primed position in which said first slideris in said stand-by position, and a depressed position in which saidfirst slider is in said piercing position.
 7. An ear piercing device asclaimed in claim 6 in which said first displacement mechanism comprisesan enclosure formed by said main body in which said trigger isreciprocally moveable along a linear trigger axis.
 8. An ear piercingdevice as claimed in claim 6 in which said first linkage comprises acompound gear comprising a driver gear on a first rack provided on saidtrigger and a driven gear on a second rack associated with said firstslider.
 9. An ear piercing device as claimed in claim 6 in which a firstnon-return ratchet is disposed between said trigger and said main bodywhich prevents movement of said trigger towards said primed positionuntil said trigger is in said depressed position.
 10. An ear piercingdevice as claimed in claim 9 in which said first non-return ratchetcomprises a sheath provided on said main body and a rod associated withsaid trigger for relative reciprocal movement in said sheath in unisonwith movement of said trigger on said first displacement mechanism, inwhich said rod comprises a plurality of radially outwardly extendingteeth and said sheath comprises a plurality of radially inwardlyextending ratchet slots for engaging said plurality of teeth in anon-return manner, in which said plurality of teeth extend onlypartially around said rod circumferentially and said ratchet slotsextend only partially around said sheath circumferentially, in whichsaid rod comprises a radially outwardly extending boss and said sheathcomprises a radially inwardly extending guide slot in which said boss isdisposed, in which said guide slot extends in an axial direction of saidsheath and comprises a first portion, second portion, third portion andfourth portion, in which said first portion is axially linear anddetermines a first axial rotational position of said boss when saidtrigger is in said primed position and when said trigger is travellingfrom said primed position to said depressed position, in which in saidfirst axial rotational position of said boss said teeth are axiallyaligned with said ratchet slots, in which said second portion extends ina helical direction of said sheath and transmits linear movement of saidrod in said sheath into a first axial rotation of said boss from saidfirst axial rotational position to a second axial rotational position inwhich said teeth are axially displaced from said ratchet slots, in whichsaid third portion is axially linear and determines said second axialrotational position of said boss when said trigger is in said depressedposition and when said trigger is travelling from said depressedposition to said primed position, and in which said fourth portionextends in a helical direction of said sheath and transmits linearmovement of said rod in said sheath into a second axial rotation of saidboss from said second axial rotational position back to said first axialrotational position.
 11. An ear piercing device as claimed in claim 9 inwhich at least one first spring member is disposed between said triggerand said main body which biases said trigger towards said primedposition.
 12. An ear piercing device as claimed in claim 6 in which saidmain body comprises a trigger housing and a needle cartridge removablymounted thereon, in which said needle cartridge comprises said firstslider, first track, piercing needle, second slider, second track andstud member, in which said first linkage comprises a first drive bodydisposed in said trigger housing, in which movement of said trigger fromsaid primed position to said depressed position moves said first drivebody from a start position to an end position, in which said firstslider comprises a first interface portion, in which said first drivebody comprises a second interface portion, and in which said firstinterface portion interfaces with said second interface portion whensaid needle cartridge is mounted to said trigger housing, such thatmovement of said first drive body is transmitted to said first slider.13. An ear piercing device as claimed in claim 2 in which said handle isconnected to said sliding jaw by a second linkage so movement of saidhandle is transmitted thereto, in which said handle is mounted on asecond displacement mechanism provided on said main body and is movablebetween a rearward position in which said sliding jaw is in said openposition and a forward position in which said sliding jaw is in saidclamping position.
 14. An ear piercing device as claimed in claim 13 inwhich a second non-return ratchet is disposed between said handle andsaid main body, in which said second non-return ratchet comprises arack, a pawl member and a release mechanism, and in which said secondnon-return ratchet prevents movement of said handle towards saidrearward position unless said release mechanism is activated.
 15. An earpiercing device as claimed in claim 14 in which a second spring memberis disposed between said handle and said main body which biases saidhandle towards said rearward position.
 16. An ear piercing device asclaimed in claim 13 in which said main body comprises a trigger housingand a needle cartridge removably mounted thereon, in which said needlecartridge comprises said first slider, first track, piercing needle,second slider, second track, stud member and clamp, in which said secondlinkage comprises a second drive body disposed in said trigger housing,in which movement of said handle from said rearward position to saidforward position moves said second drive body from a primary position toa secondary position, and in which said sliding jaw comprises a thirdinterface portion, in which said second drive body comprises a fourthinterface portion, in which said third interface portion interfaces withsaid fourth interface portion when said needle cartridge is mounted tosaid trigger housing, such that movement of said second drive body istransmitted to said sliding jaw.